138644493663 has 8 divisors (see below), whose sum is σ = 199079273008. Its totient is φ = 85319688384.

The previous prime is 138644493629. The next prime is 138644493677. The reversal of 138644493663 is 366394446831.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 138644493663 - 2¹⁰ = 138644492639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138644493563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1777493470 + ... + 1777493547.

It is an arithmetic number, because the mean of its divisors is an integer number (24884909126).

Almost surely, 2^138644493663 is an apocalyptic number.

138644493663 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

138644493663 is a deficient number, since it is larger than the sum of its proper divisors (60434779345).

138644493663 is a wasteful number, since it uses less digits than its factorization.

138644493663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3554987033.

The product of its digits is 26873856, while the sum is 57.

The spelling of 138644493663 in words is "one hundred thirty-eight billion, six hundred forty-four million, four hundred ninety-three thousand, six hundred sixty-three".